Why the Gold Line Opening Was Delayed
The Gold Line in Little Tokyo | Photo by STERLINGDAVISPHOTO via the LAist Featured Photos pool on Flickr
A Neon Tommy investigation has revealed why the Gold Line's opening was delayed, despite being ahead of schedule in construction. Basically, electrical shorts caused trains to "unpredictably switch tracks." The USC internet news site was given the run around by Metro, but it eventually obtained 40 pages of documents that led to their recent story. In part, here's what happened:
First mention of the electrical leakage issue came in an Aug. 10 update from Metro's CEO Art Leahy to the board of directors. The problem occurred at three different track crossovers -- a pair of switches connects two parallel rail tracks, allowing one train on a track to cross over to another track. The intersections : 1st Street and Clarence Avenue; 3rd Street and Ditman Avenue; and 3rd Street and Woods Avenue. Testing showed that paint containing iron oxide was causing the electrical shorts. Two problems made it worse. First, the contractor, Eastside Light Rail, placed wires within colored concrete slabs.
Regular concrete is a mixture of cement, gravel, sand and water, and is gray. Color pigments, known as iron oxide, are then added. Iron oxide, which is highly conductive, created the light tan color that Metro desired for the concrete, and probably caused the area around the wiring to be highly conductive as well. The second problem turned up when tests revealed a lack of insulation around the wires within those colored concrete slabs. That insulation generally ensures that whatever is outside of the wires does not conduct electricity with the actual wires themselves, causing a short circuit.
Because there was improper insulation, then, short circuits did in fact occur.